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1、BRITISH STANDARD BS 4773-1.1: 1991 Methods for Testing and rating air terminal devices for air distribution systems Part 1: Aerodynamic testing Section 1.1 Testing under laboratory conditions Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI B
2、S 4773-1.1:1991 This British Standard, having been prepared under the direction of the Refrigeration, Heating and Air Conditioning Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on 28 February 1992 BSI 12-1999 The following BSI references r
3、elate to the work on this standard: Committee reference RHE/2 Draft for comment 89/73460 DC ISBN 0 580 18613 X Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Refrigeration, Heating and Air Conditioning Standards Policy Committee (RHE/-)
4、 to Technical Committee RHE/2, upon which the following bodies were represented: Association of Consulting Engineers Chartered Institution of Building Services Engineers Department of Health Department of the Environment (Property Services Agency) Department of the Environment (Building Research Est
5、ablishment) Heating and Ventilating Contractors Association Heating, Ventilating and Air Conditioning Association Hevac Association Society of British Gas Industries Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 200
6、6, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 BSI 12-1999i Contents Page Committees responsibleInside front cover Forewordii 1Scope1 2Definitions1 3Symbols and suffixes5 4Instrumentation6 5Testing to determine pressure/flow rate characteristics of a supply air terminal device10 6Testing to determin
7、e pressure/flow rate characteristics of an exhaust air terminal device14 7Test to determine the area factor18 8Tests to measure the air discharge characteristics of a supply air terminal device18 9Report format26 Appendix A Example of a suitable test report27 Figure 1 Supply of air with a temperatur
8、e equal to the room air temperature3 Figure 2 Supply of air with a temperature (a) colder or (b) warmer than the room air temperature3 Figure 3 Air supply from a ceiling-mounted air terminal device, which may provide one, two or several air jets3 Figure 4 Air supply from an air terminal device where
9、 the diffusion distribution is circular4 Figure 5 Air supply from an air terminal device with vertical direction of the air jet4 Figure 6 Specimen meter scale8 Figure 7 Test installation A11 Figure 8 Pitot-static tube locations for the measurement of total pressure in test installations A and C12 Fi
10、gure 9 Test installation B13 Figure 10 Test installation C15 Figure 11 Test installation D17 Figure 12 Air terminal device positions for tests to measure envelope characteristics20 Figure 13 Determination of path of maximum velocity in discharge airstream22 Figure 14 Determination of envelope23 Figu
11、re 15 Typical plot for determination of envelope boundary point23 Figure 16 Typical plot for determination of throw25 Figure 17 Typical plot for determination of spread26 Figure 18 Typical plot for determination of rise and drop26 Table 1 Minimum accuracies for flow meters6 Table 2 Minimum accuracy
12、and maximum scale intervals of pressure-measuring instruments7 Table 3 Vertical traverse interval21 Publication(s) referred toInside back cover Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 ii BSI 12-1999 Foreword This Par
13、t of this British Standard has been prepared under the direction of the Refrigeration, Heating and Air Conditioning Standards Policy Committee to provide methods for the aerodynamic testing of air terminal devices used in air distribution systems. It supersedes BS 4773-1:1971, which is withdrawn. Th
14、e specified tests are for the determination of: a) pressure/flow rate characteristics; b) area factor; c) air discharge characteristics under isothermal conditions and in the cooling mode. Other Sections of the standard in the course of preparation will cover: Section 1.2: Laboratory methods of meas
15、uring conditions in the occupied zone; Section 1.3: Performance rating in relation to comfort criteria. Part 2 of this standard covers acoustic testing. In preparing this revision of Part 1 due regard has been taken of the International Standard ISO 5219 on laboratory aerodynamic testing and rating
16、of air terminal devices. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages
17、 This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 28, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.
18、Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 BSI 12-19991 1 Scope This Section of BS 4773-1 describes methods for the laboratory aerodynamic testing of air terminal devices and the assessment of their performance over a r
19、ange of operating conditions. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard, the following definitions apply. 2.1 treated space an enclosure served by an air distribution system 2.2 occupie
20、d zone a portion of the treated space in general occupation geometrically limited to no closer than 0.15 m to all walls and within a height of 1.8 m above the floor 2.3 supply the air flow entering the treated space 2.4 exhaust the air flow leaving the treated space. Exhaust may take one or more of
21、the following forms a) extract. Exhaust in which the air is discharged to atmosphere. b) relief. Exhaust in which the air is allowed to escape from the treated space should the pressure in the space rise above a specified level. c) recirculation. Exhaust in which the air is returned to the air treat
22、ment system. d) transfer. Exhaust in which air passes from the treated space to another treated space. 2.5 air terminal device a component of the installation that is designed to ensure the predetermined movement of air into or from a treated space, e.g. grille, diffuser etc. It is associated with a
23、n air distribution system and located in an opening provided at the boundaries of the treated space 2.6 supply air terminal device an air terminal device through which air enters a treated space. It usually consists of a deflecting member or members that impart specific direction(s) to the air strea
24、m (jet) entering the treated space and ensure efficient mixing of the supply air with the air of the treated space 2.7 exhaust air terminal device an air terminal device through which air leaves the treated space 2.8 air diffuser a supply air terminal device usually placed in the ceiling and general
25、ly circular, square or rectangular in form, and composed of divergent deflecting members 2.9 slot air terminal device a device with single or multiple components, with an aspect ratio of 10 : 1 or greater for each slot, the aspect ratio being the ratio of length and width of the enclosed rectangular
26、 opening a slot may or may not have an adjustable member to vary the direction of the air jet(s) or air flow rate Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 2 BSI 12-1999 2.10 grille an air terminal device with multiple
27、 passages for air, but without a damper 2.11 linear air terminal device an air terminal device with multiple passages contained within a rectangular frame having an aspect ratio of 5 : 1 or greater 2.12 nozzle an air terminal device so designed as to give low energy loss and thus to produce a maximu
28、m throw with minimum entrainment NOTESee 2.20. 2.13 flow equalizers components, such as turning vanes, straightening elements, perforated plates, screens etc., which, used as part of an air terminal device, even out the air velocity and/or decrease the relative magnitude of fluctuations characterist
29、ic of the air flow 2.14 core that part of an air terminal device located within a convex closed surface of minimum area inside of which are openings through which the air can pass 2.15 nominal size the recommended dimensions of the prepared opening into which the air terminal device is to be fitted
30、2.16 standard air atmospheric air having a density of 1.2 kg/m3 at 20 C, 101 325 N/m2 (1013.25 mbar) and 65 % r.h. 2.17 supply air the air entering a supply air terminal device from an upstream duct 2.18 exhaust air the air leaving an exhaust air terminal device 2.19 envelope the geometrical surface
31、 in an air stream where the local measured air velocity has the same specified value 2.20 throw (for a supply air terminal device) the distance between the centre of the core and a plane that is tangential to a specified envelope and perpendicular to the intended direction of flow (See Figure 1 to F
32、igure 5.) for radial air projection the throw is known as the radius of diffusion (See Figure 4.) Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 BSI 12-19993 Figure 1 Supply of air with a temperature equal to the room air t
33、emperature Figure 2 Supply of air with a temperature (a) colder or (b) warmer than the room air temperature Figure 3 Air supply from a ceiling-mounted air terminal device, which may provide one, two or several air jets Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, U
34、ncontrolled Copy, (c) BSI BS 4773-1.1:1991 4 BSI 12-1999 2.21 drop (for a supply air terminal device) the vertical distance between the centre of the core and the lowest horizontal plane tangential to a specified envelope (See Figure 1 to Figure 3.) 2.22 rise (for a supply air terminal device) the v
35、ertical distance between the centre of the core and the highest horizontal plane tangential to a specified envelope (See Figure 2.) 2.23 spread (for a supply air terminal device) the maximum distance between two vertical planes tangential to a specified envelope and perpendicular to a plane through
36、the centre line of the core (See Figure 1, Figure 3 and Figure 5.) Figure 4 Air supply from an air terminal device where the diffusion distribution is circular Figure 5 Air supply from an air terminal device with vertical direction of the air jet Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 0
37、1 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 BSI 12-19995 2.24 isothermal the test condition in which the supply and exhaust air temperatures are at substantially the same value 2.25 non-isothermal the test condition in which the supply and exhaust air temperatures are at s
38、ubstantially different values. In the cooling mode, the supply air temperature is lower than the exhaust air temperature 3 Symbols and suffixes 3.1 Symbols The following nomenclature is used throughout this standard: SymbolQuantity Corresponding SI unit Dimensions a, bDimensions of rectangular duct
39、cross sectionmL AdArea corresponding to the nominal size of the duct to which the device is fitted m2L2 AfFree area of air terminal devicem2L2 AnNeck area of circular or square diffuserm2L2 Ak k factor area m2L2 bRWidth of test roommL DDuct diametermL DeEquivalent diametermL DhHydraulic diametermL H
40、Height of air terminal device mounting platemL hRHeight of test roommL LDistance between air terminal device and plane of pressure measurement in test duct mL lDistance of pitot-static tube location from centre of rectangular duct mL lRLength of test roommL nLength of linear grille or diffusermL pAb
41、solute static pressurePaML1T2 paAtmospheric pressurePaML1T2 pdVelocity pressurePaML1T2 psStatic gauge pressure (p pa)PaML1T2 prStagnation (or absolute total) pressurePaML1T2 ptTotal pressure (pr pa)PaML1T2 %psStatic gauge pressure differencePaML1T2 qvVolume rate of flowm3/sL3T1 RArea parameter that
42、relates to effective size of device under test m2L2 rRadius of pitot-static tube locations in circular ductmL qv vk - - Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 6 BSI 12-1999 3.2 Suffixes The suffixes used in this Bri
43、tish Standard are as follows. a) D Value corrected to take account of test duct pressure loss b) m Mean value c) u Refers to flow measuring station d) 1 Refers to measuring position in test duct 4 Instrumentation 4.1 Volume flow rate measurement 4.1.1 Accuracies Air flow meters shall have accuracies
44、 at least as precise as those shown in Table 1. Table 1 Minimum accuracies for flow meters NOTEAir flow meters that comply with BS 1042-1.1 and BS 1042-1.2 will satisfy the requirements for accuracy given in Table 1 and do not require calibration. 4.1.2 Checking 4.1.2.1 Air flow meters shall be chec
45、ked before their initial use and subsequently at intervals not exceeding 12 months. One of the following methods of checking shall be employed. 4.1.2.2 For flow meters complying with BS 1042-1.1 and BS 1042-1.2, all critical dimensions shall be measured. If any of the measured dimensions does not co
46、mply with the standard, then the air flow meter shall either be dimensionally corrected or be calibrated in accordance with 4.1.2.3 before further use. SLinear parameter that relates to effective size of device under test mL vVelocitym/sLT1 vkk factor velocitym/sLT1 vxMaximum velocity at distance x
47、from centre of supply air terminal device m/sLT1 WWidth of air terminal device mounting platemL XThrowmL XcAxis of velocity measurement in direction of throwmL xDistance from centre of supply air terminal device in direction of throw mL YSpreadmL YcAxis of velocity measurement in direction of spread
48、mL ZDrop (or rise)mL ZcAxis of velocity measurement in direction of drop/risemL Loss coefficientdimensionless number Thermodynamic temperatureKF Densitykg/m3ML3 Flow rate rangeAccuracy of measurement Below 0.007 m3/s 0.0009 m3/s 0.007 to 0.07 m3/s 5 % Above 0.07 m3/s 2.5 % SymbolQuantity Correspondi
49、ng SI unit Dimensions qv Ak - - Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:16:37 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4773-1.1:1991 BSI 12-19997 4.1.2.3 Other air flow meters shall be calibrated against a flow meter complying with BS 1042-1.1 and BS 1042-1.2 or by using the pitot-static traverse technique described in BS 1042-2.1. The calibration shall be for a minimum of five flow rates equally spaced throughout the range of the flow m